Inductance device



July 12,1927. 1,635,541

F. CONRAD INDUCTANCE DEVICE Filed July 24, 1925 I BY TTYOIRNEY- PatentedJuly 12, 19.21.

UNITED STATES PATENT orrica.

rm; coNa'an, or rrrrsaunen, PENNSYLVANIA, ASBIGNOB 'ro wns'rmenousnnLac'rnIc a murac'ruame comm, a oonroaa'rIoN or PENNSYLVANIA.

DTDUGIAIGI DEVICE Application am m p4, 1m. Serial o. 45,179.

M invention relates to inductance devices,

' particularly to inductors for use with highfrequency apparatus.

It is an object of my invention to produce 5 aninductor in which thelosses shall be reduced to a, minimumpeven at very high: fre-z quencies.V

It is a further, object of my invention to provide an inductor suitablefor use with heavy currents at high-ire uency.

' It is a further ob]ect of my invention to providemeans'for securing inplace a copper strap wound into a coil upon a non-metallic support. v

It is a further object of my invention to provide means by which thewindinghmay be out re-i secured upon an insulating core wit sort tovarnish or other a hesive.

It is a further object of my mve ntion to provide means by which awinding in the form of-a metallic strap and a core in the form of avitreous or other frangible substance, may be securely united.

Other objects of the invention and details 26 of the construction willbe apparent from the following description and t e accompanying drawing,in which Figure 1 is a side view, a portion of the strap being brokenaway.

.30 Fig. 2 is an end view, and

- Fig. 3 is a detail showing the strap in sec-' tion. s

The core or support upon which the coil is wound is preferably in theform of a cylinder, although the, IIIVGIItlOIllS applicable" to an.columnar form. In the form illustrat the sup ort is a hollowcylinder 1of an suitable su stance, such as fused quartzz,

e outer surface of the cylinder is-pro- 40 vided with a groove 2. If thecylinder is made by casting or molding, the groove may be formed at thesame time.- Ifv the substance of which the cylinder is made is such thatthe groove cannot be thus formed with sufiicient accuracy, it"may madeor finished byTgrinding.

causes little dielectric loss, even, when subjected to intense fields athigh frequency.

Because no cementation material is present, no dielectric losses areintroduced by the means fastening the winding to itssupport.v

A cylinder of vitreous or mineral substance, such as marble porcelainor'fused quartz is i beat adapted ior large sizes" For sma 'er upon thecore.

said support.

sizes, hard rubber is suitable When the of copper. The strap is providedwith'an at offset rib or groove 6 which extends lengthwise of the strap.1 As the stra is wound upon the cylinder, the offset 6 ts into thegroove 2 and properlyvpositions the winding At one end the strap issecured to the c linder by a binding post 4 andv at the ot er .end byanother binding 0st. Other bind- 1 ing posts may be provi' ed beside theend 'ones and, when so provided, the st ap should be perforated toreceive them., he several binding posts afi'ord convenient means forattaching the conductor bywhich current is brought to the inductor. Bychanging suchconductors from one binding post to another, i

the number of turns inthe inductor may be altered.

It will be apparent to those skilledin the art that many modificationsmay be made without departing from the principles of this 86 invention.The specific illustration and de'-' scription of a single "form is,therefore, not

:to be considered, a limitation; I

. 'I claim as myinvention:

1. In a coil, a support, a flat conductive o strip having alongitudinally depressed por tion. wound along said support, and meansextending along said su(ppo rt in-juxtaposi tion to a portion of saistrip between the edges thereof for positioning. said strip upon 2. In a0011,41. conductive ribbon, said ribbon having "a longitudinallyextending offset portion, a support, and. means 'on sai supportco-operating with said oflsetporo ort. t a

'3. A coil silipport comprising a hollow cylinder of ins ating materialhaving small dielectric losses; said cylinder having a heli- 106 calgroove of arcuate cross section and opena circuit connecting device. no

, tion for positioning said ribbon on said sup e cylinder must be ofa'material which p .x. In combination, e coil su port comprising ahollow cylinder of insu atin material having small dielectric losses,sai cylinder having a helical groove of arcuate cross secf tion, aconductive strip having an ercuete I 5.- An an article of manufacture, aconduc- 10 tive ribbon having a longitudinally extendin'g depressionadapted to cooperate with a supporting structure and to strcngtl'iensaid ribbon against bending.

In testimony whereof, I have hereunto 15 subscribed my name this 8th dayof July,

FRANK CONRAD.

